The Wyborg operation was a part of the Wyborg-Petrozavodsk strategic offensive, executed to ensure safe passage of goods being passed from Murmansk to the rest of the USSR and the destruction of Finnish forces in the immediate vicinity of Leningrad, continuously threatening it.
The operation was executed by forces of the right wing of the Leningrad Front (commanded by Army General L.A. Govorov, Marshall after June 18th, 1944), the Red Banner Baltic Fleet, and Ladoga Military Fleet. The goal was driving the enemy from the Karelo-Finnish SSR and the north parts of the Leningrad region, restoring the pre-war border with Finland.
June 10th, 1944, is considered the official start date of the operation, but Soviet artillery began its barrage on June 9th, lasting about 10 hours, and recce in force with elements of the 10th and 92nd Infantry Divisions of the 92nd Army. As a result of the battles, the enemy was forced out of the salients at Mertut and Duna settlements.
On June 10th, after a secondary artillery barrage that lasted two and a half hours, the 21st Army advanced into battle. During the day, the army penetrated 12 kilometers of Finnish defenses. The enemy took heavy losses, was demoralized, and began retreating into the forests.
On June 11th, Soviet forces occupied the settlements of Terijoki and Raivola. Around Kivenappa, elements of the 30th Guards Infantry Corps encountered fierce resistance from a Finnish tank division, armed primarily with captured T-26 and T-28 tanks. Taking advantage of the lack of decisive action from Soviet forces, the Finns managed to push back the Soviet advance and hold their defenses for several hours. After regrouping for a joint assault with tanks and artillery, the Soviets drove the Finns out of this territory and forced them to retreat.
By June 20th, fighting was happening in Wyborg and its outskirts. Enemy resistance was split into several parts, and the Finns were forced to retreat to the Wyborg-Kuparsaari-Taipale line.
On June 21st, Soviet forces began the Svir-Petrozavodsk operation, the second part of the Wyborg-Petrozavodsk strategic offensive, which concluded on August 9th in a Soviet victory. On August 25th, 1944, Finland sued for peace, and on September 4th, an order was issued to cease combat action against the USSR, and on September 25th, a peace treaty was signed with the USSR.
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